This article proposes a novel multidimensional Taylor network (MTN)‐based adaptive finite‐time control approach for stochastic nonlinear systems with input saturation constraints. First, by ...introducing the hyperbolic tangent function, a piecewise smooth function is proposed to approximate the input saturation constraints, which can solve the problem caused by input saturation. Then, with the aid of MTN approximation theorem, a novel adaptive finite‐time control approach is proposed, which can guarantee that all signals of the closed‐loop system are semi‐globally finite‐time stability in probability (SGFTSP), the system output follows the given reference signal, meanwhile, the tracking error converges to a small neighborhood of the origin in finite‐time. Compared with the existing results, the proposed approach has the characteristics of simple structure and low calculation, which can achieve the satisfactory control performance with a reduced computational burden. In the end, the effectiveness of the proposed approach is validated by Lyapunov stability theory and two simulation experiments.
Bio and nanomaterials based on Fe3O4 Xu, Jia-Kun; Zhang, Fang-Fang; Sun, Jing-Jing ...
Molecules,
12/2014, Letnik:
19, Številka:
12
Journal Article, Book Review
Recenzirano
Odprti dostop
During the past few years, nanoparticles have been used for various applications including, but not limited to, protein immobilization, bioseparation, environmental treatment, biomedical and ...bioengineering usage, and food analysis. Among all types of nanoparticles, superparamagnetic iron oxide nanoparticles, especially Fe3O4, have attracted a great deal of attention due to their unique magnetic properties and the ability of being easily chemical modified for improved biocompatibility, dispersibility. This review covers recent advances in the fabrication of functional materials based on Fe3O4 nanoparticles together with their possibilities and limitations for application in different fields.
In this brief, an adaptive robust finite-time tracking control (ARFTTC) scheme for trajectory tracking of a fully actuated marine surface vehicle with unknown disturbances is proposed. A new ...finite-time disturbance observer is incorporated into the proposed finite-time tracking control (FTTC) structure that facilitates faster convergence and better robustness to disturbances. Hence, in the presence of unknown disturbances, the ARFTTC can cause tracking error to converge to zero in a finite time. Simulation studies and comprehensive comparisons with conventional backstepping technique demonstrate remarkable performance and superiority of the ARFTTC in terms of both tracking accuracy and robustness.
Wearable sensors are increasingly finding their way into applications of kinesthetic sensing, personal health monitoring, and smart prosthetics/robotics. A graphene‐based composite fiber sensor with ...a “compression spring” structure is fabricated, featuring the ability of detecting multiple kinds of deformation. This fiber sensor is integrated into wearable sensors for monitoring human activities and intricate movements of robotics successfully.
To investigate the association of miR-106b-5p with neuroinflammation and microglial activation in a status epilepticus (SE) mouse model. We examined changes in the expression of microRNA-106b-5p ...(miRNA-106b-5p), repulsive guidance molecule A (RGMa), triggering receptor expressed on myeloid cells 2 (TREM2), and the microglia-related markers interleukin (IL)-1β, IL-4, IL-6, IL-10, inducible nitric oxide synthase (iNOS), and arginase-1 (Arg-1) in the mouse hippocampus of the lithium–pilocarpine-induced SE mouse model. Eighty-four female C57BL/6 mice were randomly divided into a normal control group (
n
= 12), and six SE groups (
n
= 12/group), which were monitored at 6 h and at 1, 3, 7, 14, and 21 days (d) post-SE induction. Unlike in the dentate gyrus, immunohistochemical staining revealed prominent neuronal swelling at 6 h, significant neuronal loss and apoptosis on day 3, and recovery by day 14 in the hippocampal
cornu ammonis
(CA)1 and CA3 pyramidal cells in SE mice. We noted elevated levels of miRNA-106b-5p and all microglia-related markers, which peaked at 3 days post-SE, except IL-4, which peaked at 7 days post-SE, indicating inflammation and microglial activation. RGMa and TREM2 levels decreased at 6 h post-SE. All markers but miRNA-106b-5p, RGMa, and TREM2 returned to baseline levels at 21 days post-SE. Dual luciferase reporter gene assay showed that microRNA-106b-5p can interact with RGMa. We observed that miR-106b-5p level increased while both RGMa and TREM2 levels decreased post-SE and showed associations with microglial activation and inflammation in the mouse hippocampus, suggesting their potential as SE therapeutic targets.
Genetic markers have emerged as one of the most promising tools for species identification and geographic traceability in biodiversity conservation and international trade of biological products. ...However, traditional molecular markers rarely have sufficient resolution at lower taxonomic levels, especially for discriminating closely related forest tree species and their populations. In this study, we developed a panel of RNA‐Seq based single nucleotide polymorphism (SNP) markers for tracing the geographic origin of an endangered conifer, Cathaya argyrophylla, which is a paleoendemic restricted to four mountain regions in subtropical China. A total of 69 individuals from five populations (DLS, SHS, HP, BMS, and DYS) covering the entire range were used for transcriptome sequencing. Based on these transcriptomic data, we evaluated genetic variation and population structure of C. argyrophylla, and found extremely low nucleotide diversity but strong population differentiation. We also screened 113 population‐specific SNP loci, including 96 for BMS, eight for DYS, six for SHS, two for HP, and one for one of the three subpopulations from DLS. According to these geographically diagnostic SNPs, we designed four population‐specific molecular barcodes for PCR amplification. To test the utility and efficiency of the four markers in geographic discrimination, double‐blind experiment was performed using 157 individuals labelled without any locality information. We found that almost all tested individuals could be successfully assigned to their geographic localities. Our study not only sheds some new light on the genetic profile of C. argyrophylla, but also provides a practical and cost‐efficient solution for geographic traceability using transcriptome‐derived SNPs.
We demonstrate a narrow-linewidth, high side-mode suppression ratio (SMSR) semiconductor laser based on the external optical feedback injection locking technology of a femtosecond-apodized ...(Fs-apodized) fiber Bragg grating (FBG). A single frequency output is achieved by coupling and integrating a wide-gain quantum dot (QD) gain chip with a Fs-apodized FBG in a 1-μm band. We propose this low-cost and high-integration scheme for the preparation of a series of single-frequency seed sources in this wavelength range by characterizing the performance of 1030 nm and 1080 nm lasers. The lasers have a maximum SMSR of 66.3 dB and maximum output power of 134.6 mW. Additionally, the lasers have minimum Lorentzian linewidths that are measured to be 260.5 kHz; however, a minimum integral linewidth less than 180.4 kHz is observed by testing and analyzing the power spectra of the frequency noise values of the lasers.
Photo thermal power generation, as a renewable energy technology, has broad development prospects. However, the operation and scheduling of photo thermal power plants rarely consider their internal ...structure and energy flow characteristics. Therefore, this study explains the structure of a solar thermal power plant with a thermal storage system and analyzes its main energy flow modes to establish a self-operation and low-carbon scheduling optimization model for the solar thermal power plant. The simulation results of the example showed that for the self-operating model oriented towards power generation planning and peak valley electricity prices, the existence of a thermal storage system could improve the power generation capacity and revenue of the photovoltaic power plant. For example, when the capacity of the thermal storage system was greater than 6 h, the penalty for insufficient power generation in the simulation result was 0 $, and the maximum increase in revenue reached 84.9% as the capacity of the thermal storage system increased. In addition, when the capacity of the thermal storage system increased from 0 to 8 h, the comprehensive operating cost decreased from 1635.2 k $ to 1224.6 k $, and the carbon emissions decreased from 26.4 × 10
3
ton to 22.1 × 10
3
ton. Compared with the existing literature, this study provides a more comprehensive and systematic solution through detailed energy flow analysis and optimization model. The research has practical and far-reaching significance for promoting the development of clean energy technology, improving the sustainable utilization of renewable energy, and optimizing the overall performance of the energy system.
Signaling pathways are critical modulators of a variety of physiological and pathological processes, and the abnormal activation of some signaling pathways can contribute to disease progression in ...various conditions. As a result, signaling pathways have emerged as an important tool through which the occurrence and development of diseases can be studied, which may then lead to the development of novel drugs. Accumulating evidence supports a key role for extracellular signal-regulated kinase 1/2 (ERK1/2) signaling in the embryonic development of the central nervous system (CNS) and in the regulation of adult brain function. ERK1/2, one of the most well characterized members of the mitogen-activated protein kinase family, regulates a range of processes, from metabolism, motility and inflammation, to cell death and survival. In the nervous system, ERK1/2 regulates synaptic plasticity, brain development and repair as well as memory formation. ERK1/2 is also a potent effector of neuronal death and neuroinflammation in many CNS diseases. This review summarizes recent findings in neurobiological ERK1/2 research, with a special emphasis on findings that clarify our understanding of the processes that regulate the plethora of isoform-specific ERK functions under physiological and pathological conditions. Finally, we suggest some potential therapeutic strategies associated with agents acting on the ERK1/2 signaling to prevent or treat neurological diseases.